Arrangement for arresting landing ariplanes by means of a wire



Nov. 24, 1964 P. B. FONDEN ETAL ARRANGEMENT FOR ARRESTING LANDINGAIRPLANES BY MEANS OF A WIRE Filed Jan. 10, 1963 if ,s 'a 57,478,,

w Walla United States Patent M 3,158,342 ARRANGEMENT FOR ARRESTWGLANDEJG AHRPLANES BY MEANS 0F A WIRE Per Borje Fonden, Hejdegaten 3, andKarl Gve Torgny W aiander, Vasavagen 49, both of Liniroping, SwedenFiled Jan. 1%, 1963, Ser. No. 250,513 Ciairns priority, applicationSweden, May 23, I962, 5,776/62 4 Claims. (Cl. 244-410) The presentinvention relates to an arrangement for arresting landing aeroplanes bymeans of a wire, net or the like connected to brakes disposed on eitherside of a landing runway.

Upon arresting a landing aeroplane by means of a hook engaging thearresting cable, the stability of the arresting operation must not beignored. An excessively asymmetrical loading will subject the aeroplaneto jerks winch, on landing, are unpleasant to the pilot who willinstinctively attempt to correct the movement, resulting in an increasedasymmetry involving the possibility of de-tireing, and where theasymmetry is great, this involves the direct risk of the aeroplanecanting over, especially if it is one provided with a narrowundercarriage. These problems can be met by feeding out equal lengths ofthe arresting wire from both brakes. The slippage which may, in thiscase, occur at the hook, if for example, the aeroplane does not contactthe arresting wire squarely at the center but slightly laterallythereof, will produce forces which tend to stabilize the aeroplane.

Because of this, in some arresting devices, such as are used on boardaircraft carriers for example, a single brake has been employed to acton the arresting wire on both sides of the runway. In the case ofaeroplane carriers no substantial problem is involved in providing thespace required for this purpose below the landing deck. For groundairports the corresponding arrangement is sometimes employed which,however, results in extremely expensive installation cost, since thewire must be passed underground from the brake disposed at one side ofthe runway, below the runway and over to the opposite side thereof. Inorder to avoid any trouble due to differential elasticity of the wireson one or the other side, it is, in addition, often necessary to resortto the solution of providing an artificial length on the shorter side.This will result in an increase of the masses of inertia which will haveto be set in motion. One way of reducing these masses is to dispose thebrake centrally beneath the runway, but in such case too, the cost ofinstallation will be materially increased.

The present invention is mainly characterized in that the brakes forboth sides of the arresting wire are interconnected by an endless wire,chain, cable or similar flexible element for synchronizing therotational speeds of the brakes during the arresting operation. Adistinct advantage following from the invention resides in the fact thatthe brakes may be connected on or above the landing runway, whereby theinstallation will be simple and easy to be made at existing runways,since the runway need not be closed 01f during the period required formaking the installation.

The synchronizing wire may be one of substantially smaller dimensionthan the arresting wire and braking wires, since only a portion of thebraking load will be transmitted from one brake to the other. Such asmall gauge wire can be placed on the runway without any risk. If thehook of the aeroplane which is intended to engage the arresting wireshould fail to properly engage it, it will not hook onto the small gaugesynchronizing wire disposed beyond it. Even greater safety to preventthis will be attained if the synchronizing wire is flattened and isplaced with its flat face directed toward and is lying against thesurface of the landing runway.

With the above-stated objects, and other objects which may hereinafterappear in view, we have utilized the ar rangement of parts to bedescribed and moreparticularly pointed out in the claims appendedhereto.

In the accompanying drawing, wherein an illustrative embodiment of theinvention is disclosed,

FIG. 1 shows diagrammatically the structure and operation of theimproved aeroplane arresting apparatus;

FIG. 2 is a vertical sectional view of a brake drum having two groovesfor respectively receiving the arresting cable and the synchronizingcable;

FIG. 3 shows a brake drum having two grooves for a flat arresting cableand a similar synchronizing cable;

FIG. 4 shows how a synchronizing cable is arranged in a manner to liefiat against the surface of a'runway, and

FIG. 5 shows how the synchronizing cable is caused to be disposed belowthe landing surface or runway.

In the drawing and with particular reference to FIG. 1, the numerals 1and 2 designate brake drums disposed on either side of a landing runway.Brake wires 3 and 4 are wound around the respective drums 1 and 2, saidwires being connected by an arresting or catching Wire 5. When thelanding aeroplane contacts the wire 5 by the engagement of the hook onthe aeroplane with said wire, the wires 3 and 4 and the connected wire 5are resistantly let out from the brakes.

The brake drums I and 2 are connected by an endless synchronizing wire 6encircling the drums. The direction of approach of an aeroplane isindicated by the arrow 7. The synchronizing wire 6 is disposed on therunway forwardly of the arresting Wire 5, as seen in the direction ofapproach of the aeroplane. This is made possible by extending the wire 6over guide pulleys 8, 9, 10 and II which are located in advance of thebrake drums I and 2.

Designated at 12 is a pneumatic or hydraulic wiretensioning device whichis anchored to the runway and is connected to the guide pulley ill. Thistension device has the dual function of first, tensioning the Wire 6 inconjunction with the plane interception, so that upon movement of thewire 6, air or liquid under pressure will in a well-known manner, heapplied to the wire tensioner, causing the latter to attract the guidepulley 10, and second, to limit the tension exerted on the wire 6 sothat its strength limit will not be exceeded. Owing to the fact that thewire 6 is not initially tensioned, it will normally lie on the surfaceof the runway, and it thus cannot, especially if it is fiat, get caughtby the catching hook of the aeroplane. Upon the outset of the catchingoperation the wire 6 becomes tensioned and it is thereby lifted abovethe surface of the runway and prevented from abrasively contacting orscraping against the same. FIG. 4 shows how the synchronizing cable 6 isarranged to lie flatly against the face of the runway or landingsurface. The cable therein shown is a fiat band and it is turned so thatits face lies parallel to the face of the landing surface by means ofthe rollers 13 which are spaced away from the pulleys 8 and 9 so thatthe fiat band, constituting the cable 6 will be turned In this view ofthe drawing the tensioning device 12 is shown as applied to the pulley 9rather than to the pulley It as in FIG. 10.

Althoughthe simplest installation can be obtained with the synchronizingwire lying on the runway, it will be within the scope of the presentinvention to dispose the wire below the surface of the runway. In FIG. 5is shown the manner in which the synchronizing cable or wire may belocated beneath the runway or landing surface. Therein the brake 1 islocated above the landing surface as are the pulleys 8 and 9. The cable,after leaving the pulleys 8 and 9, passes through apertures 15 in therunway 16 to Patented Nov. 24, 1964 all reach the under side of thelanding surface or runway where it is guided by the pulleys 13.

As shown in FIG. 2, the brake drums 1 and 2 are each provided with twogrooves indicated respectively at 1'7 and 18. The groove shown at 17receives the arresting wire 3 and the groove shown at 18 receives thesynchronizing cable 63. The drum shown in PEG. 3 shows how a fiat bandused in place of the arresting wire 3 is received in groove 1% with thesynchronizing band serving as cable 6 received in the groove Eha.

Having thus described an embodiment of the invention, it is obvious thatthe same is not to be restricted thereto, but is broad enough to coverall structures coming Within the scope of the annexed claims.

What we claim is:

1. An arrangement for arresting landing aeroplanes by means of a Wire orthe like constituting an arresting device, said wire being connected tobrakes disposed on either side of the landing runway, the brakes beingconnected by an endless cable separate from the arresting wireconstituting a flexible element for synchronizing the rotational speedsof both of the brakes during the arresting operation.

2. An arrangement for arresting landing aeroplanes as provided for inclaim 1, characterized in that the syn- 4 chronizing cable is placed onthe landing runway beyond the arresting wire as seen in the direction ofapproach of a landing aeroplane, the cable being extended about guidepulleys.

3. An arrangement for arresting landing aeroplanes as provided for inclaim 1, wherein the synchronizing cable is disposed below the landingsurface.

4. An arrangement for arresting landing aeroplanes comprising, a pair ofspaced-apart brakes having rotative drums, an arresting cable extendingbetween the brakes, pulleys located forwardly of the brakes in thedirection of the landing movement of an aeroplane, an endlessbrake-synchronizing cable separate from the arresting cable extendingaround the brake drums and engaging With the pulleys, said cable beingdisposed below the arresting cable, and a tension device operative onthe synchronizing cable to tension the same during theaeroplane-arresting operation.

References Cited in the file of this patent UNITED STATES PATENTS2,967,683 Crater Jan. 10, 1961 2,789,780 Cotton et a1. Apr. 23, 19573,086,735 Radovitz et al. Apr. 23, 1963

4. AN ARRANGEMENT FOR ARRESTING LANDING AEROPLANES COMPRISING, A PAIR OFSPACED-APART BRAKES HAVING ROTATIVE DRUMS, AN ARRESTING CABLE EXTENDINGBETWEEN THE BRAKES, PULLEYS LOCATED FORWARDLY OF THE BRAKES IN THEDIRECTION OF THE LANDING MOVEMENT OF AN AEROPLANE, AN ENDLESSBRAKE-SYNCHRONIZING CABLE SEPARATE FROM THE ARRESTING CABLE EXTENDINGAROUND THE BRAKE DRUMS AND ENGAGING WITH THE PULLEYS, SAID CABLE BEINGDISPOSED BELOW THE ARRESTING CABLE, AND A TENSION DEVICE OPERATIVE ONTHE SYNCHRONIZING CABLE TO TENSION THE SAME DURING THEAEROPLANE-ARRESTING OPERATION.